Electric illuminating apparatus



June 6, 1933. w. F. WESTENDORP' ,1

ELECTRIC ILLUMINATING APPARATUS Filed Dec. 17, 1932 Inventor: W i l lemF Westendorp H is Attorney.

Patented J nine 6, 1933 UNITED STATES 1 PATENT OFFICE WILLEH F.WBTEHDOBP, O1 SCHENECTADY, NEW YORK, ASSIGNOB GENERAL ELEC- TRIOCOMPANY, A CORPORATION OF NEW YORK ELEO'I'BIC III-OHINATING APPABATU SApplication filed December 17, 1982. Serial No. 847,769.

My invention relates to electric illuminating apparatus. Moreparticularly it relates to electric discharge illuminating apparatusoperable from a source of single phase alternating current. One objectof my invention is the provision of improved illuminating apparatus ofthis character which will operate on a single phase circuitwithoutproducing visible flicker. Another object of my invention is theprovision of improved apparatus of this character the illumination fromwhich may be made to resemble that from some other source. Thisapplication is a continuation-in-part of my copending application SerialNo. 547,156, filed June 26, 1931, for

Electric illuminating apparatus.

My invention will be better understood from the-following descriptiontaken in connection with the accompanying drawing, and

its scope will be pointed out in the appended claims.

In the single figure of the drawing which illustrates an embodiment ofmy invention I have shown at 1 and 2 two similar positive 2 columndischarge lamps each of which comprises a suitable envelope of glass orquartz containing a gas or vapor or a suitable gaseous mixture whichbecomes luminous when subjected to an electric discharge. Various gasesand vapors may be used for this purpose depending largely upon theparticular kind of light which it is desired that the lamp shallproduce; for example, the .gas or vapor may be argon, neon, helium,krypton, xenon, mercury or sodium. Lamp 1 has the hot cathode 3 and mainanode 4. Similarly, lamp 2 has a hot cathode 5 and main anode 6.Forstarting'purposes both lamps are provided with a series of auxiliaryelectrodes 7 which connect with the mainanodes of the respective lampsthrough resistances 8 whose value may, for example, be 2000 ohms, 1000ohms, 500 ohmsand 250 ohms, counting from the cathode to the main anode.connected respectively with the two sides 9 and 10 of the alternatingcurrent supply circuit which, for example, may be at 110 volts or 220volts and have a frequencyof 7 cycles. Each cathode is provided with aner that the core is ma The hot cathodes 3 and 5 are shown directlyheater, one end of which is connected with the cathode and the other endconnected with i the opposite side of the supply circuit whereby eachheater connects'directlyacross the supply circuit. The main anodes 4 and'6 56 .connect through the reactor 12, now to be described, with thesides 10 and 9 respectively of the alternating current supply "which iscontrolled by switch 11.

Reactor 12 comprises the core '13 upon which is wound a .bifilar windingcomprising the two coils 14 and '15, coil 14 being arranged in serieswith the main anode 4 and coil 15 being arranged in series with the mamanode 6. Incircuit with the respect ve 00118 14 and 15 are thecontrolling resistances 16 and 17. The two coils 14 and 15 comprisingthe bifilar winding of reactor 12 are connected in the circuit in such amanetized in the same sense by therectifi currents passing through eachof the lamps. As the flux linkages tend to remain constant the sum ofthe absolute value of the currents through the two coils will tend toremain constant the result of which is that currents of approxi-' matelyrectangular wave shape pass through the lamps with no interval betweenthe successive waves, which currents have a 180 phase displacementrelative to each other the total light output from the two lamps beingconstant neglecting a slight ripple.

When the above described apparatus is thrown on the alternating currentsupply circuit as byclosing switch 11, the cathodes of the two lamps areheated. and by reason of the ionizing effect of the auxiliary anodes thedischarge quickly travels up each lam to the main anode thereof everycycle al though on difierent half cycles for the two lamps. Since theresistances in series with 'the auxiliary anodes are large a very smallcurrent only passes to each during the operiation of the lamp. As eachlamp rectifies the current taken by it and as. the lam s are connected..to the supply circuit reverse y, the current flows in the samedirection in the two coils 14 and 15.

Instead of employing a reactor having a bifilar w1nd1ng I may in certaincases employ a reactor having a winding comprising two separated coilson an open core in which case there is suflicient coupling between thecoils to cause an overlapping of the light impulses from the two lamps.Because of the leakage reactance, the wave shape is more triangular andless rectangular in form, the

base portions of the triangles overlapping. With such a construction thelight never reduces to a zero value but the ripple is larger than wherea reactor having a bifilar winding is used.

Each of the two. lamps 1 and 2- may contain various gases or vapors suchas those mentioned above depending upon the character of light desired.For the purpose of producing illumination which resembles that from someknown source or gives the sensation thereof I employ gases or vapors inthe respective lamps such that the combined light from the two lampswill have the desired character. For producing the sensa'- tion ofdaylight I may, for example, use neon in one lamp and mercuryvapor inthe other, the two lamps taken together as a unit thereby providing acombination of red and green rays which give to a person the sensationwhich is substantially the same as that produced by daylight.

I have chosen the particular embodiment described above as illustrativeof my invention and it will be apparent that various other modificationsmay be made without departing from the spirit and scope of my inventionwhich modifications I aim to cover by the appended claims:

What I claim as new and desire to secure by Letters' Patent of theUnited States is:

1. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternating current supply circuitcomprising a plurality of rectifying discharge lamps, means connectingsaid lamps to said circuit in parallel and in a relatively reversemanner, and a reactor in the connecting means having windings arrangedto produce fluxes in the same sense.

2. Electric discharge apparatus for pro ducing illumination withoutvisible flicker from a single phase alternating current supplycomprising a plurality of discharge lamps connected in parallel acrosssaid supply to operate respectively on the positive and negative halfwaves thereof, and a reactor having inductively related windings each intheconnection of one of said lamps and arranged to produce fluxes in thesame sense.

3. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternating current supplycomprising a plurality of discharge lamps each having a cathode and ananode, means connectin the cathode of one lamp and the anode o the otherlamp to one side of the supply, means for connecting the other cathodeand anode to the other side of the supply, and a reactor having aplurality of windings in the connections of the respective lamps, saidwindings being arranged to produce fluxes in the same sense.

4. Electric discharge apparatus for pro- .ducing illumination withoutvisible flicker from a single phase alternating current supplycomprising a plurality of discharge lamps connected in parallel acrosssaid supply to operate respectively on the positive and negative halfwaves thereof and a reactor comprising a core having a plurality ofwindings thereon connected in series with the respective lamps andarranged to magnetize the core in the same sense.

5. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternating current supplycomprising a plurality of discharge lamps connected in parallel acrosssaid supply to operate respectively on the positive and negative halfwaves thereof and a reactor having bifilar windings each in series withone of said lamps and arranged to produce fluxes in the same sense.

6. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternating current supplycomprising a plurality of discharge lamps each having a cathode and ananode, means for connecting the cathode of one lamp and the anode of theother lamp to one side of the supply, means for connecting the othercathode and anode to the other side of the supply, and a reactorcomprising a core havin bifilar windings thereon, said windings eing inseries with the respective anodes and connected to magnetize the core inthe same sense.

7 Electric discharge apparatus for producing illumination withoutvisible flicker from an alternati g current supply circuit, comprising aplurality of rectifying discharge lamps each having a cathode, a mainanode and a starting anode, said lamps being reversely connected withsaid circuit in parallel, and a reactor in the connection of said lampswith the circuit havin a plurality oi windings arranged to pro ucefluxes in the same sense.

8. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternating current supply circuit,comprising a plurality of rectifying discharge lamps reversely connectedwith the circuit in parallel, a bifilar reactor and limiting resistancessaid reactor and resistances being arranged in the connections of saidlamps with the circuit and both windings of the reactor being arrangedto magnetize the core of the reactor in the same sense.

9. Electric discharge apparatus for producing illumination withoutvisible flicker from a single phase alternatin current supply circuit,comprising a plura 'ty of rectifyin discharge lamps each having a hotcathe, a main anode and an auxiliary starting anode, said lamps beingconnected in parallel across said circuit and the respective cathodesbeing connected with the opposite sides of the circuit, a reactor havinga plurality of inductively related windings on the same core connectedin circuit with the main anodes of the lamps and arranged to magnetizethe core in the same direction, and a limiting resistance in each anodecircuit. 7 10. Electric discharge apparatus for producing illuminationwithout visible flicker from a single phase alternating current supplycircuit comprising a plurality of rectify ing discharge lamps, meansconnecting said lamps to said circuit in parallel in a relativelyreverse manner, and a reactorin the connecting means having windingsarranged to K produce fluxes in the same sense, one of said lampscontaining neon and another containing mercury va or whereby thecombined light resembles a light. I

11. Electric disc argeapparatu'sfor producing villumination whichresembles da light and without visible flicker from a single 1 phasealternating current suppI circuit,

comprising a plurality of recti ying discharge lamps reversely connectedwith the circuit in parallel, a bifilar reactor and limiting resistancessaid reactor and resistances being arranged in the connections of saidlamps with the circuit and both windings of the reactor being arrangedto magnetize the core of the reactor in the same sense, one of saidlampscontaining neon and the other containing mercury vapor. In witnesswhereof, I have hereunto set my hand.

WILLEM F. WESTENDORP.

